[Libguestfs] [PATCH libnbd 6/7] lib/crypto.c: Don't use empty vector
getlogin_r() with empty buffer will always fail since the underlying
array is NULL. Reserve space before using the vector.
Signed-off-by: Nir Soffer <nsoffer(a)redhat.com>
---
lib/crypto.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/lib/crypto.c b/lib/crypto.c
index 2ce4d4d..09d98fd 100644
--- a/lib/crypto.c
+++ b/lib/crypto.c
@@ -141,6 +141,12 @@ nbd_unlocked_get_tls_username (struct nbd_handle *h)
}
for (;;) {
+ /* Increase capacity (str.cap starts at 0) */
+ if (string_reserve (&str, 16) == -1) {
+ set_error (errno, "realloc");
+ free (str.ptr);
+ return NULL;
+ }
if (getlogin_r (str.ptr, str.cap) == 0) {
return str.ptr;
}
@@ -149,12 +155,6 @@ nbd_unlocked_get_tls_username (struct nbd_handle *h)
free (str.ptr);
return NULL;
}
- /* Try again with a larger buffer. */
- if (string_reserve (&str, 16) == -1) {
- set_error (errno, "realloc");
- free (str.ptr);
- return NULL;
- }
}
}
--
2.31.1